Compound
Methanol
A small alcohol released not by fermentation but by enzymes stripping methyl groups off pectin, which is why juice handling rather than yeast choice governs how much a cider contains.
Also called Methyl alcohol.
- Class
- Alcohols
- Formula
- CH3OH
- How often it matters
- Occasional
What it does in cider
- Is liberated whenever pectin methylesterase de-esterifies pectin, so its concentration tracks pectin breakdown rather than sugar conversion.
- Rises with maceration time, with pectinase addition and with fruit that has been held long enough for its own enzymes to work.
- Contributes nothing perceptible to aroma or taste at the concentrations cider reaches — it is a marker of what happened to the pectin, not a flavour compound.
- Concentrates in the early fraction of a distillation, which is why it matters to Calvados and other apple spirits in a way it does not to cider.
Measured figures
Shown as they were measured, with the context each was taken in. They are not averaged: a concentration recorded in one country's fruit in one decade is not a constant.
Methanol40.0–87.0 mg/L
Villaviciosa, Asturias, Spain, 2001–2002 · 4 samples · Gas chromatography with flame ionisation detection · Suárez Valles, Pando Bedriñana, Fernández Tascón, Querol Simón and Rodríguez Madrera, Food Microbiology 24(1):25–31
Traced by the authors to the raw material rather than to the ferment — methanol comes off the pectin in the fruit, not out of the yeast. The harvest changed the figure by a factor of two while the pressing technology barely moved it.
Released when pectin is de-esterified, so it tracks the fruit and the enzyme rather than anything the yeast did. Measured in milligrams per litre.
What forms it
Processes that put this compound into the drink, or increase how much of it is there.
Pectinase treatment
Adding pectin-degrading enzyme preparations to juice so that haze-forming and viscosity-forming pectin is broken down before fermentation.
Maceration
Holding milled pomace before pressing so that phenolics, aroma precursors and pectin have time to move out of the solid tissue and into the juice.
Keeving
Forming a floating pectin gel that lifts nutrients and solids out of the juice, so that the ferment starves before it finishes and leaves natural sweetness behind.
Enzyme addition to pomace
Dosing pectin-degrading enzyme into milled pomace rather than into juice, to raise press yield and change how the cake drains.
Pomace conditioning
Letting milled pomace stand before it goes to the press so that it drains better, presses faster and gives more juice.
About Methanol
Pectin is a chain of galacturonic acid units, many of them capped with a methyl ester group. Remove that cap — which is exactly what pectin methylesterase does, whether the enzyme comes from the fruit itself or from a commercial preparation added to the juice — and the methyl group leaves as methanol. Every cider therefore contains some, in the tens to low hundreds of milligrams per litre, and a cider made from long-macerated pomace or from enzyme-treated juice contains more than one pressed quickly from fresh fruit.
The practical consequence for cider is small, because methanol at those concentrations is neither tasted nor smelled and is present in comparable amounts in ordinary fruit juice. The consequence for distillation is not small. Distilling concentrates the volatile fraction, and methanol runs early, which is why apple spirit production is regulated with methanol limits and why the heads cut in a Calvados still is a technical requirement rather than a stylistic one.
The interesting inversion is that the practices which produce the most methanol are also the ones a cidermaker may most want. Keeving depends on pectin methylesterase acting on juice pectin — the whole process is built on de-esterification — and long maceration before pressing improves both yield and phenolic extraction. In cider these are choices with no drinking consequence; in a still they are choices that have to be managed downstream.
Related compounds
Compounds it is formed from, converted into, confused with, or routinely met alongside.
Polysaccharides
Pectin
The structural polysaccharide of fruit cell walls, which decides how much juice a press releases, whether a cider ever clears, and whether keeving is possible at all.
Enzymes
Pectin methylesterase
The enzyme that strips methyl groups from pectin, exposing the charged sites that calcium bridges — which is the reaction the whole of keeving is built on.
Acids
Galacturonic acid
The sugar acid that pectin chains are built from, released as they break down, and a significant part of why juice from rotten fruit binds so much of the sulphite added to it.
Polysaccharides
Calcium pectate
The gel formed when calcium bridges de-esterified pectin chains, which floats to the surface as the brown cap of a keeve and carries the juice’s nutrients out with it.
What people ask next
Questions readers ask about the things this page mentions. Each one goes to the section that answers it rather than to a page written to receive the question.
- What does pectin do in cider — Pectin is the structural polysaccharide that holds fruit cells together. In juice it holds haze in suspension, and it is the molecule keeving depends on: strip its methyl groups and it will gel with calcium and float the nutrients out of the juice.
- What is keeving — Keeving is a technique for starving a ferment of nitrogen so that it stops before all the sugar is gone, leaving a naturally sweet cider. Pectin is made to gel and float as a brown cap, carrying nutrients and yeast out of the juice with it.
- What is maceration in cider making — Maceration is letting milled pomace stand before pressing, so that enzymes soften the tissue and phenolics and aroma move from the skins into the juice. It raises both colour and tannin, and raises the risk of oxidation with them.
- Why add pectic enzyme to cider — Pectic enzyme breaks down the pectin that holds a haze in suspension and makes juice hard to press, so the cider clears and the yield rises. It must not be used where a keeve is intended, because keeving depends on the pectin staying intact.
- What is pectin methylesterase — It is the fruit’s own enzyme that strips methyl groups from pectin, freeing the carboxyl groups that then cross-link with calcium to form a gel. That reaction is the chemical basis of keeving, and it also releases methanol.
- What is pomace conditioning
Where to go next
- All compounds — Grouped by what the fruit brings and what the ferment makes of it.
- Sensory — Every descriptor, with the compound or process that causes it.
- Microbiology — The organisms whose metabolism most of this chemistry belongs to.
Sources
What this page rests on. Where a source is marked as registered rather than read, CiderHQ is recording that the body is authoritative on the subject without claiming to have worked through the document itself. See our evidence policy for what each state means.
The Science of Cidermaking and associated technical writing
Andrew Lea · reference work · passage verified 2026-08-24
Written by a food chemist who worked at Long Ashton on apple phenolics. Unusual among specialist cider writing in that it is primary-research-adjacent: the author is describing work he did, and cites the literature. This is why it is registered at tier 1 for chemistry while a general cider book is not.
Hochschule Geisenheim University — beverage technology
Hochschule Geisenheim · university · retrieved 2026-08-24
German beverage-technology research covering apple wine and fruit juice processing, including the enzymology of clarification.
Institut Français des Productions Cidricoles (IFPC)
IFPC · research institute · retrieved 2026-08-24
The French technical institute for cider production. The authority for the French cultivar classification families, for keeving as an industrial process, and for the pectin and nitrogen chemistry that keeving depends on.